-/* FIXME move this */
-static void queue_bio(struct mirror_set *ms, struct bio *bio, int rw);
-
-#define MIN_REGIONS 64
-#define MAX_RECOVERY 1
-static int rh_init(struct region_hash *rh, struct mirror_set *ms,
- struct dm_dirty_log *log, uint32_t region_size,
- region_t nr_regions)
-{
- unsigned int nr_buckets, max_buckets;
- size_t i;
-
- /*
- * Calculate a suitable number of buckets for our hash
- * table.
- */
- max_buckets = nr_regions >> 6;
- for (nr_buckets = 128u; nr_buckets < max_buckets; nr_buckets <<= 1)
- ;
- nr_buckets >>= 1;
-
- rh->ms = ms;
- rh->log = log;
- rh->region_size = region_size;
- rh->region_shift = ffs(region_size) - 1;
- rwlock_init(&rh->hash_lock);
- rh->mask = nr_buckets - 1;
- rh->nr_buckets = nr_buckets;
-
- rh->buckets = vmalloc(nr_buckets * sizeof(*rh->buckets));
- if (!rh->buckets) {
- DMERR("unable to allocate region hash memory");
- return -ENOMEM;
- }
-
- for (i = 0; i < nr_buckets; i++)
- INIT_LIST_HEAD(rh->buckets + i);
-
- spin_lock_init(&rh->region_lock);
- sema_init(&rh->recovery_count, 0);
- atomic_set(&rh->recovery_in_flight, 0);
- INIT_LIST_HEAD(&rh->clean_regions);
- INIT_LIST_HEAD(&rh->quiesced_regions);
- INIT_LIST_HEAD(&rh->recovered_regions);
- INIT_LIST_HEAD(&rh->failed_recovered_regions);
-
- rh->region_pool = mempool_create_kmalloc_pool(MIN_REGIONS,
- sizeof(struct region));
- if (!rh->region_pool) {
- vfree(rh->buckets);
- rh->buckets = NULL;
- return -ENOMEM;
- }
-
- return 0;
-}
-
-static void rh_exit(struct region_hash *rh)
-{
- unsigned int h;
- struct region *reg, *nreg;
-
- BUG_ON(!list_empty(&rh->quiesced_regions));
- for (h = 0; h < rh->nr_buckets; h++) {
- list_for_each_entry_safe(reg, nreg, rh->buckets + h, hash_list) {
- BUG_ON(atomic_read(®->pending));
- mempool_free(reg, rh->region_pool);
- }
- }
-
- if (rh->log)
- dm_dirty_log_destroy(rh->log);
- if (rh->region_pool)
- mempool_destroy(rh->region_pool);
- vfree(rh->buckets);
-}
-
-#define RH_HASH_MULT 2654435387U
-
-static inline unsigned int rh_hash(struct region_hash *rh, region_t region)
-{
- return (unsigned int) ((region * RH_HASH_MULT) >> 12) & rh->mask;
-}
-
-static struct region *__rh_lookup(struct region_hash *rh, region_t region)
-{
- struct region *reg;
-
- list_for_each_entry (reg, rh->buckets + rh_hash(rh, region), hash_list)
- if (reg->key == region)
- return reg;
-
- return NULL;
-}
-
-static void __rh_insert(struct region_hash *rh, struct region *reg)
-{
- unsigned int h = rh_hash(rh, reg->key);
- list_add(®->hash_list, rh->buckets + h);
-}
-
-static struct region *__rh_alloc(struct region_hash *rh, region_t region)
-{
- struct region *reg, *nreg;
-
- read_unlock(&rh->hash_lock);
- nreg = mempool_alloc(rh->region_pool, GFP_ATOMIC);
- if (unlikely(!nreg))
- nreg = kmalloc(sizeof(struct region), GFP_NOIO);
- nreg->state = rh->log->type->in_sync(rh->log, region, 1) ?
- RH_CLEAN : RH_NOSYNC;
- nreg->rh = rh;
- nreg->key = region;
-
- INIT_LIST_HEAD(&nreg->list);
-
- atomic_set(&nreg->pending, 0);
- bio_list_init(&nreg->delayed_bios);
- write_lock_irq(&rh->hash_lock);
-
- reg = __rh_lookup(rh, region);
- if (reg)
- /* we lost the race */
- mempool_free(nreg, rh->region_pool);
-
- else {
- __rh_insert(rh, nreg);
- if (nreg->state == RH_CLEAN) {
- spin_lock(&rh->region_lock);
- list_add(&nreg->list, &rh->clean_regions);
- spin_unlock(&rh->region_lock);
- }
- reg = nreg;
- }
- write_unlock_irq(&rh->hash_lock);
- read_lock(&rh->hash_lock);
-
- return reg;
-}
-
-static inline struct region *__rh_find(struct region_hash *rh, region_t region)
-{
- struct region *reg;
-
- reg = __rh_lookup(rh, region);
- if (!reg)
- reg = __rh_alloc(rh, region);
-
- return reg;
-}
-
-static int rh_state(struct region_hash *rh, region_t region, int may_block)
-{
- int r;
- struct region *reg;
-
- read_lock(&rh->hash_lock);
- reg = __rh_lookup(rh, region);
- read_unlock(&rh->hash_lock);
-
- if (reg)
- return reg->state;
-
- /*
- * The region wasn't in the hash, so we fall back to the
- * dirty log.
- */
- r = rh->log->type->in_sync(rh->log, region, may_block);
-
- /*
- * Any error from the dirty log (eg. -EWOULDBLOCK) gets
- * taken as a RH_NOSYNC
- */
- return r == 1 ? RH_CLEAN : RH_NOSYNC;
-}
-
-static inline int rh_in_sync(struct region_hash *rh,
- region_t region, int may_block)